As promised. Here are 3 quickies with my phone. Neither muffler touches any part of the bumper or the lower trim piece.
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They look much better with the eye and when cleaned and polished. Lots of rain yesterday so a nice coating of road splash on them at the moment.
I believe the muffler shop I used charged me about $100 to install - no extra parts or modifications needed. They simply swapped them out at the flange.